Fundamentals and behaviour in commodity prices: Kemp

Fundamental changes in supply and demand account for less than a third of short-term movements in commodity futures prices, according to an authoritative new study by researchers at UNCTAD and the Swiss Federal Institute of Technology.
Reflexive trading, when prices respond to past price changes rather than new information about fundamentals, now accounts for 60 to 70 percent of price moves in the main futures contracts, up from less than 40 percent before 2005………………………………………..Full Article: Source